We propose to develop a fluidics-based automated sorter for microtransponders to complement the existing line of PharmaSeq instruments and reagents. PharmaSeq provides ultra-small light-powered microtransponders and a fluidics-based bench-top flow reader as tools to perform complex bioassays. The microtransponders are 500x500 micron and 250x250 micron electronic chips, produced with standard CMOS processes, and contain photocells for power, digital logic, memory for an ID, and an RF transmitting antenna. The chips are self-contained, and function well in wet or dry conditions. The main project goal is to produce a sorter which uses cross-flow to route chips to a selected output port based on the microtransponder ID. This preferred method employs low pressure regulators, solenoid valves, transport liquid, and the low mass chips as the only moving parts, suggesting that high-speed, high-reliability, low-cost sorting systems are feasible. The sorter will contain an ID reader to identify a microtransponder and a router module to manipulate it. An automatic sorter would enable combinatorial chemistry on microtransponders, accelerating drug discovery. The sorter, in a parallel application, will also reduce the cost of microtransponder kits for DNA and protein multiplex assay.